Sotalol hydrochloride is a non-selective competitive β-adrenergic receptor blocker that also exhibits Class III antiarrhythmic properties by inhibiting potassium channels. Sotalol hydrochloride is currently indicated as a treatment for delay in recurrence of atrial fibrillation/atrial flutter and documented life-threatening ventricular arrhythmias. It is marketed in tablet form as Betapace and Betapace AF.
Some patients, such as children and the elderly, cannot swallow solid dosage forms. In order to provide sotalol hydrochloride to such patients, oral formulations must be prepared extemporaneously, typically at a compounding pharmacy. These oral formulations are suspensions and typically containing 5 mg/mL of sotalol hydrochloride prepared by compounding a Betapace AF tablet and simple syrup. Alternative formulations are suspensions containing 5 mg/mL of sotalol hydrochloride prepared by compounding Betapace with commercially available vehicles including Ora-Plus (which contains microcrystalline cellulose, sodium carboxymethylcellulose, xanthan gum, carageenan, sodium phosphate and citric acid), Ora-Sweet (which contains sucrose, glycerin, sorbitol, citrus-berry flavor, sodium phosphate and citric acid) and Ora-Sweet SF (which contains glycerin, sorbitol, sodium saccharin, xanthan gum, citrus-berry flavor, citric acid and sodium citrate) and are also described in Sidhom, M. B., et al., International Journal of Pharmaceutical Compounding, Vol. 9, No. 5, 2005, pp. 401-406.
Unfortunately, these extemporaneous oral suspensions have limited stability, i.e., only three (3) months when stored at controlled room temperature and ambient humidity.
Accordingly, there remains a need for oral formulations of sotalol hydrochloride suitable for patients that cannot swallow solid dosages that have improved stability suitable for commercial sales.